Before Tuesday's gay marriage victories in four states, a majority of voters consistently rejected it. Is this a blip, or a monumental sea change that signals broader change?

Four years ago, opponents of gay marriage celebrated a winning streak, having persuaded California voters to end marriage rights for gays. If courts or legislatures bowed to the pro-marriage forces, the opposition figured it could just go to the ballot box to restore marriage bans.

But all that changed Tuesday, when gay marriage supporters succeeded in the four states where the question was on the ballot. Until then, voters had consistently opposed marriage rights, most recently in May in North Carolina.

The opposing sides differed on the significance, with Christian conservatives considering the election a blip and gay rights activists describing it as a monumental sea change. But the results emboldened activists to target other states for marriage rights and left their opponents reeling.

Gay rights activists singled out President Obama's change of heart in favor of same-sex marriage as a key ingredient in Tuesday's victories. Just four years ago, the sponsors of Proposition 8's ban on same-sex marriage made robocalls to California homes with a recording of Obama saying he opposed gay nuptials.

"His shift caused a lot of other politicians to feel free to change their positions as well and made it easier for African American churches to change their positions," said Jon W. Davidson, legal director for Lambda Legal, a gay rights organization.

With election victories in Maine, Maryland, Minnesota and Washington, gay rights activists said Wednesday that they would focus next on winning marriage rights both in the federal courts and in state legislatures, which could include states such as Rhode Island, Delaware, Hawaii and Illinois.

"When you have momentum on your side, it's the time to double down," said Chad Griffin, who launched the legal fight against Proposition 8. "That's exactly what we've got to do: We've got to take this momentum and move forward."

Gay rights supporters spent about $32.7 million in Tuesday's races, compared with $11.3 million by Christian conservatives. Four years ago, the spending on Proposition 8 was about equal on both sides. Activists said the Mormon Church largely stayed out of the races this time, letting the Roman Catholic Church carry the burden.

Supporters of same-sex marriage also enlisted the backing of churches and the African American community, which in the past tended to oppose gay marriage.

In Maryland, where African Americans make up about 30% of the population, a black megachurch helped spur support for marriage rights. An exit poll showed that 27% of voters were African American, and half supported marriage rights, according to the Human Rights campaign, a gay rights advocacy group.

Activists also changed their messaging from four years ago. Instead of asking voters for equal rights, they emphasized that gays, like heterosexuals, wanted to formalize their commitment and protect their children. Volunteers shared personal testimonials about their partners and family during nightly phone banks and door-to-door canvassing.

"We turned this into a conversation about love, family and commitment," said Griffin, head of the Human Rights Campaign.

Proposition 8 is now before the U.S. Supreme Court, which is considering whether to review a federal appeals court decision that overturned the 2008 ballot imitative. Gay rights lawyers said Tuesday's election demonstrates to the court that public opinion on same-sex marriage is moving rapidly in favor of gay rights.

"This will send an even clearer message to the justices about which way the winds of history are blowing," Davidson said. "And I think it may raise questions in their mind about whether to even take the case."

Opponents of same-sex marriage blamed their defeats on the Democratic nature of the states in play on Tuesday and the lopsided spending in favor of marriage rights.

"The other side is now going to try to pass more marriage laws, and we will have to work twice as hard," said Brian Brown, president of the National Organization for Marriage, which spent $5.5 million on Tuesday's ballot measures. "Today is a bad day for us."

Frank Schubert, who ran the campaign against gay marriage in all four states, downplayed the results as coming from "very liberal, deeply blue" states and insisted the issue remained hotly contested throughout the country.

"The American people continue to view marriage as a union between one man and one woman," Schubert said. "There's nothing about last night that changes that. There's no sea change in the country."

Tuesday's election also brought more liberals to the Legislature in Illinois, where state Rep. Greg Harris says he expects to introduce a bill supporting same-sex marriage in 2013. The Democrat introduced a bill on the issue this year that did not pass.

"The climate has changed in a huge way," Harris said in a postelection phone call, according to the newspaper Crain's Chicago Business.